Ornusa Usanno, Suthasinee Chaisilapasung, Nopphadol Sukrakanchana, and Kitjakarn Supamattaya

pp. 187 - 197

Abstract

In the present study an 8-week feeding trial was conducted on sex-reversed red tilapia (Oreochromis
niloticus x O. mossambicus) to assess the effects of diets containing various levels (i.e. 0, 50, 100, 500, 1,000
and 2,500 ppb) of aflatoxin B₁ (AFB₁) on growth performance, blood parameters and histopathology of fish.
Results showed that experimental fish fed AFB₁ with 2,500 ppb showed significant reduced weight gain and
hepatosomatic index. However, feed supplemented with AFB₁ caused no effect on survival rate of the fish in
each group. Feeding high level of AFB₁ (1,000 and 2,500 ppb) also affected some blood parameters i.e.
hemoglobin and plasma protein. Some histopathological changes (i.e. cloudy swelling, inflammation and cell
necrosis) were observed in liver and pancreas of fish fed AFB₁ with 1,000 and 2,500 ppb. The severity of symptoms was related with concentration of AFB₁. This indicated that AFB₁ may impair the functioning of
fish hepatocytes. However, no residue of AFB₁ was detected in fish tissues at completion of the feeding period.
It can be concluded that fish feeds occasionally contaminated with AFB₁ directly affected fish health but
may have no negative impact on fish consumers.